Hey, I'm Guilherme Illescas 馃憢

I'm a Senior Software Engineer specializing in high-performance web applications with exceptional user experiences.

Experience

My professional journey

Jul 2024 - Presente

1 ano 4 meses

Senior Software Engineer

AwSales 路 Tempo integral

AwSales is an AI-powered sales platform that automates WhatsApp outreach, recovers leads, runs campaigns, and integrates with tools like Hotmart and Assiny. It lets customers build custom webhooks, create knowledge bases for high-accuracy AI assistants, test agents in a playground, and review full message histories.

- Frontend development for the customer platform: design and ship production features, refactor key flows, fix high-impact bugs, and co-define UX with Product and Design.

- Contribute to product discovery: participate in scoping sessions, propose simpler user journeys, and align roadmap with the business vision.

- Build and maintain the collaborator back-office app (internal tooling) with Nuxt (Vue) and Node, improving day-to-day operational visibility and efficiency.

- Implement and maintain core integrations on the client platform, including Stripe and Meta's WhatsApp API.

- Collaborate across two squads: (1) customer platform (5 devs, 1 QA, 1 designer, 1 PO, 1 tech lead) and (2) back-office (1 PO, 1 tech lead, 1 dev).

- Advocate for code quality and speed: pragmatic refactors, component reuse, and consistent UI patterns with Tailwind + React Query.

- Work fully remote, async-first, documenting decisions and keeping tight iteration loops with PO/Tech Lead.

Tech & Tools:

Next.js, React, React Query, Tailwind CSS, Prisma, Nuxt (Vue), Node.js, Stripe, Meta WhatsApp API, Google Cloud (GCP), Docker, GitHub Actions (CI/CD), Figma.

Next.jsReact QueryVue.jsNode.jsReact.js
Nov 2023 - Set 2025

1 ano 11 meses

Senior Software Engineer

Previdenciarista 路 Terceirizado

I am responsible for maintaining applications to the highest standards and ensuring stability for our 27000+ active customers on the platform, enabling them to perform pension calculations and more. Additionally, I oversee the main website, ensuring it achieves the highest levels of SEO and performance.

I enhanced the website's performance by 22%, improved SEO by approximately 9%, and implemented good practices, resulting in a 29% enhancement.

- Feature development: Demonstrated experience and good hands-on programming experience Next, HTML, Tailwind CSS, Typescript and React Hooks;

- SEO improvement: Implementation of SEO techniques using Google Analytics and Google Tag Manager;

- Bug fixes: Bug-fixing initiatives, enhancing software reliability and user satisfaction;

- Code refactoring: I am responsible to reduce tones of code lines, increasing development experience and improving the efficiency;

- Testing: Build unit and e2e tests using Jest and Playwright

Out 2022 - Out 2023

1 ano 1 m锚s

Senior Software Engineer

Escola Conquer 路 Tempo integral

As the Lead Software Engineer, I spearheaded the development of the Conquer Plus Platform, a project that has significantly impacted over 2 million customers globally by issuing more than 1 million certificates. My role was pivotal in every phase of the platform's lifecycle, from the initial planning stages to the selection of cutting-edge technologies and the architecture of the entire system.

My responsibilities included:

- Led and fostered professional growth within team, driving individual advancement and overall team success;

- Implemented impactful features resulting in significant user base growth and enhanced customer engagement using Next.js, Styled-Components, HTML, Jest, Storybook, React Hooks, and Typescript;

- Addressing bugs through the use of Jest and debugging techniques;

- Implementing improvements to enhance performance, validated through Google Lighthouse;

- Planning features and system architectures;

- Improved team performance establishing and maintaining the Design System using Figma and implementation of micro-front-end with Single SPA;

- Delivered insightful presentations on key technical topics, establishing thought leadership within and beyond the team.

Ago 2022 - Mai 2023

10 meses

Co-Founder and Senior Software Engineer

Amank 路 Aut么nomo

I worked as a front-end developer and co-founder at Amank, a SaaS management platform that helped companies centralize, control, and reduce software costs. I was responsible for developing the product's interface, leveraging modern technologies to ensure usability, performance, and scalability.

Beyond coding, I actively contributed to the product planning and end-to-end development, shaping features, architecture, and user experience from the ground up.

Amank stood out in the market and was acquired by BHUB in 2024, consolidating its relevance in the SaaS ecosystem in Brazil.

Jun 2021 - Dez 2021

7 meses

Mobile Software Engineer

Dobank 路 Freelance

I was instrumental in DoBank app creation from the ground up, utilizing React Native and leveraging cutting-edge technologies to ensure unparalleled security, user experience, and usability. My strategic use of GraphQL for API integration set the foundation for efficient data management and app functionality.

- App Development and Feature Creation: Pioneered the entire app development, crafting its core features and architecture, which led to a robust platform with enhanced user engagement and satisfaction.

- Screen Development: Implementation of all app screens, focusing on intuitive user interfaces and seamless navigation.

- API Consumption with GraphQL: Engineered the app's data management system using GraphQL, optimizing performance and data retrieval.

Mar 2021 - Set 2021

7 meses

Software Engineer

Chamer Solu莽玫es em Tecnologia 路 Freelance

I was pivotal in driving innovation and development across various projects. Within a dynamic, small team environment, I specialized in feature development, e-commerce, and dashboard creation, utilizing REST APIs for seamless database integration.

- Feature Development: Creation and implementation of key features, enhancing user interaction and functionality across platforms using React and Typescript.

- E-commerce and Dashboard Development: Spearheaded the development of e-commerce platforms and data-driven dashboards, improving business operations and decision-making processes.

- Database Integration: Expertly managed database connections through REST APIs, ensuring efficient data flow and system reliability

- SEO Implementation: Implemented advanced SEO techniques to enhance online visibility and search rankings for our platforms. I improved search engine rankings by over 20%, significantly increasing organic traffic and user acquisition.

- App Performance Optimization: Focused on optimizing the performance of applications, reducing load times and improving responsiveness

Jan 2020 - Nov 2020

11 meses

Jr Software Engineer

WebTrip Viagens Corporativas

My responsibilities extended beyond traditional development roles, encompassing website maintenance, server management, and comprehensive IT support within the company. My versatile skill set allowed me to contribute significantly to both technical and operational aspects of the business.

- Servers Maintenance: Ensured high availability and reliability of company servers, minimizing downtime and supporting seamless business operations.

- Advanced Spreadsheet Automation: Leveraged Google Scripts and Google Sheets to automate complex data processes, enhancing efficiency and accuracy. I Automated over 6 internal reporting processes, reducing manual data entry time by 70% and reduce phone calls into 12%.

- Telecommunication Systems Management: Implemented and maintained telephony infrastructure, including IVR and extensions, to improve communication flow

- Website Improvements: Drove enhancements to the front and back end of the company's websites using HTML, CSS, and JavaScript, elevating user experience and performance.

- Process Improvement: Utilized Bizagi and LucidChart to refine internal processes, fostering a more efficient and transparent workflow.I Enhanced team efficiency by designing and implementing 10+ process improvements, reducing process turnaround time.

- CRM Development and Maintenance: Managed the development and upkeep of Suite CRM, ensuring its alignment with business needs and user requirements. I Customized and optimized CRM functionalities, improving sales team productivity

About

A bit more about me

User avatar

As a senior software engineer, I have designed and developed high-performance applications that have reached over 1 million users worldwide. My expertise lies in crafting seamless user experiences, optimizing performance, and building scalable solutions that drive business success.

Beyond coding, I am passionate about empowering people and fostering growth鈥攂oth in the products I develop and in the individuals I mentor. My goal is to leverage technology to create meaningful impact and transform the way people interact with digital experiences.